Absolutely. I've been rereading 'Little Girl Blue' recently and some of those A&M press releases are beyond parody in terms of their furtherance of the 'goody-fourshoes' image. It's all 'they're nice, respectful kids, they don't do drugs, they respect their elders, they're not going to threaten the establishment'. There's even a press release issued by the record company detailing their (then) new house in Newville Avenue and how it had been furnished/decorated - why on earth would anyone want details on that!? Surely it couldn't have been that hard to depict them as 'normal' without going so absurdly overboard.
Certainly, being brother and sister would always have attracted some heckles from the press, but it seems alas that A&M went out of their way to paint them in as sticky sweet and anodyne fashion as possible. The image problem originated in their own camp rather than being foisted upon them by the critics.
I'm not sure to what extent marketing and promo materials about a band, would/should matter. A music critic should care only about the music he is (allegedly) reviewing, not promo marketing materials.
Perhaps it would make it easier for the critic to make assumptions without actually listening; in which case, they aren't much of a critic.